Use 1.8mm Hole Punch Pliers or large side of the Screw Down Hole Punch

These can be tricky the first time you open and lock your first ring. Be sure to put on your glasses or use a magnifier if you need one because the locking component is quite small. You'll need two chain nose pliers to open and lock these rings into place. Once you lock them they are a done deal, so no reopening these puppies!